<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <meta http-equiv="X-UA-Compatible" content="ie=edge">
    <title>练习</title>
    <style>
        .map {
            position: relative;
            width: 747px;
            height: 617px;
            margin: 50px auto;
            background: url(./img/map.png) center no-repeat;
        }

        body {
            background-color: black;
        }

        .BeiJin {
            position: absolute;
            top: 221px;
            right: 196px;
            color: #fff;
        }

        .dotted {
            width: 5px;
            height: 5px;
            background-color: #09f;
            border-radius: 50%;
        }

        .BeiJin div[class^="pulse"] {
            /* 小波纹放在父盒子里面水平垂直居中，放大后向四周发散 */
            position: absolute;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%);
            width: 5px;
            height: 5px;
            box-shadow: 0 0 12px #009dfd;
            border-radius: 50%;
            animation: pulse 1.6s linear infinite;
        }

        .TaiBei {
            position: absolute;
            top: 495px;
            right: 82px;
            color: #fff;
        }

        .TaiBei div[class^="pulse"] {
            /* 小波纹放在父盒子里面水平垂直居中，放大后向四周发散 */
            position: absolute;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%);
            width: 5px;
            height: 5px;
            box-shadow: 0 0 12px #009dfd;
            border-radius: 50%;
            animation: pulse 1.6s linear infinite;
        }

        /* 这么写，权重不够 */
        /* .pulse2 {
            animation-delay: 0.4s;
        } */

        .pulse2 {
            animation-delay: 0.4s !important;
        }

        .pulse3 {
            animation-delay: 0.8s !important;
        }

        .a2 {
            width: 50px;
            height: 50px;
            box-shadow: 0 0 12px #009dfd;
        }

        @keyframes pulse {
            0% {}

            70% {
                /* transform: scale(5); 我们不用scale，因为他会让阴影也变大 */
                width: 40px;
                height: 40px;
                opacity: 1;
            }

            100% {
                width: 70px;
                height: 70px;
                opacity: 0;
            }
        }
    </style>
</head>

<body>
    <div class="map">
        <div class="BeiJin">
            <div class="dotted"></div>
            <div class="pulse1"></div>
            <div class="pulse2"></div>
            <div class="pulse3"></div>
        </div>

        <div class="TaiBei">
            <div class="dotted"></div>
            <div class="pulse1"></div>
            <div class="pulse2"></div>
            <div class="pulse3"></div>
        </div>

        <div class="BeiJin">
            <div class="dotted"></div>
            <div class="pulse1"></div>
            <div class="pulse2"></div>
            <div class="pulse3"></div>
        </div>

        <div class="a2"></div>
    </div>
</body>

</html>